Synthetic Gemstones and Treatments: What CAD/CAM Jewellers Need to Know

In my previous post, we explored the fundamental properties of natural gemstones and their implications for CAD/CAM jewellery design. Today, I will guide you through the fascinating world of synthetic gemstones and treatments, an area where science meets artistry, and where modern jewellers must be especially knowledgeable. Understanding these materials and processes is crucial for creating ethical, durable, and commercially successful designs in today’s evolving market.

The Science Behind Synthetic Gemstones

Synthetic gemstones represent one of the most remarkable achievements in materials science. Having closely studied their development for my book The CAD/CAM Jeweller, I find their creation process particularly relevant to digital designers who already work at the intersection of technology and traditional craft.

What many do not realise is that synthetic gems possess virtually identical chemical compositions and crystal structures to their natural counterparts. Unlike imitations that merely look similar, true synthetics share fundamental properties with natural stones. The earliest major breakthrough came in 1877 when Edmond Frémy created the first gem-quality emerald crystals, followed by Auguste Verneuil’s revolutionary flame-fusion technique for synthetic rubies in 1902.

Production methods

Flame-fusion (Verneuil): Primarily used for synthetic corundum, creating the distinctive boule form

Flux-melt technique: Ideal for emeralds and other gems requiring slower crystal growth

Hydrothermal growth: Mimics natural formation conditions for quartz and beryl varieties

Advanced diamond synthesis: Using HPHT and CVD processes to create lab-grown diamonds

When designing settings for synthetic stones in CAD software, I have found that while the physical properties match natural gems, subtle differences in inclusions and growth patterns can influence aesthetic decisions. For instance, the curved growth lines in flame-fusion stones might inspire complementary curved elements in a setting.

Gemstone Treatments and Their Impact on CAD/CAM Design

Throughout my years teaching jewellery design, I have emphasised that understanding gemstone treatments is not just academic, it directly affects how we approach digital modelling and setting design. Many of the gemstones we work with have undergone some form of enhancement.

Heat treatment: Common in sapphires, rubies, and tanzanite to enhance colour

Fracture filling: Often used in emeralds and diamonds to improve clarity

Oiling: Traditional treatment for emeralds that requires special consideration in setting design

Irradiation: Used to create coloured diamonds and blue topaz

When designing in CAD, I always consider these treatments and their implications. For instance, fracture-filled stones require settings that avoid excessive pressure points. Oiled emeralds benefit from protective bezel settings that shield them from cleaning agents that might deplete the oil. In my CAD courses, I teach students to adjust their designs based on not just what a stone is, but how it has been treated.

Ethical Considerations for the Modern Jeweller

The digital jewellery revolution has coincided with increasing consumer awareness about ethical sourcing. Synthetic gemstones offer several advantages in this regard:

Reduced environmental impact compared to mining

No connection to conflict zones or exploitative labour practices

Consistent quality and availability

Affordability, making fine jewellery more accessible

However, proper disclosure is not merely ethical, it is a legal requirement in the UK and most countries. As I explain in detail in The CAD/CAM Jeweller, understanding the terminology is crucial: synthetic or laboratory-created are appropriate terms, while simulated or imitation refer to different materials entirely.

In my CAD/CAM design practice, I have embraced synthetics not just as economical alternatives but as materials with unique creative possibilities. For instance, the perfect clarity of synthetic corundum allows for more intricate undercutting in digital models than might be advisable with included natural stones.

Future Trends: CAD/CAM and Next-Generation Gemstones

As production techniques evolve, we are seeing the development of synthetic gemstones with qualities that go beyond what is found in nature: unique colour combinations, optical effects, and even customised internal features. This presents exciting opportunities for CAD/CAM designers who can create settings specifically engineered to highlight these novel characteristics.

The younger generation of consumers is increasingly accepting of synthetic gemstones, particularly when paired with innovative designs. I predict that the combination of advanced CAD/CAM techniques and high-quality synthetics will define a significant segment of the fine jewellery market in coming years.

Conclusion

Whether working with natural, synthetic, or treated gemstones, the modern CAD/CAM jeweller needs a comprehensive understanding of gemstone properties and origins. This knowledge informs every aspect of digital design: from the thickness of prongs to the clearance beneath a stone, from the angle of facet-aligned bezels to the overall structural integrity of the piece.

Throughout my career teaching digital jewellery design, I have found that students who master both the technical aspects of CAD software and the fundamentals of gemmology consistently produce the most innovative, beautiful, and commercially successful work.